Beyerdynamic A1 Headphone Amplifier

If you find an image of the rear panel, there is a symbol that looks like a square within a square. This means that it is double insulated and has passed testing to ensure electrical isolation of the chassis. Any faults or shorts are contained within the electronics themselves and have no path to ground. This is a legitimate scheme and is used on many household electronics from hair dryers to corded drills. If this were a Chinese product I would be concerned as markings (such as double insulation and CE) are often applied illegally without the required testing to known standards. I trust Beyerdynamic as a company (and the hammer of German regulation) so that there is little doubt this product is safe. That being said, I'm not very impressed with this amp at this price point. Think I'll sit this one out.

Why does the IEC inlet only have two pins? I mean, it might cheaply and easily solve ground loop issues, but a metal chassis that is not grounded might not be safe. I would expect this to zap you with accumulated charge every time you touch it. Of course YMMV with the grounding scheme of your house.